Compared to a landplane, a seaplane’s starting procedures
are somewhat different. Before starting the
engine, the seaplane usually needs to be pushed away
from the dock, and quite often, it is the pilot who
pushes off. Therefore, the pilot should perform as
many of the items on the starting checklist as possible
prior to shoving off. This includes briefing passengers
and seeing that they have fastened their seatbelts. The
passenger briefing should include procedures for evacuation,
the use of flotation gear, and the location and
operation of regular and emergency exits. All passengers
are required to be familiar with the operation of
seatbelts and shoulder harnesses (if installed). When
the engine is primed and ready to start, the pilot leaves
the cockpit, shoves off, returns to the pilot’s seat,
quickly turns on the master switch and magnetos, verifies
that the propeller area is clear, and starts the engine. With oil pressure checked, idle r.p.m. set, and
the seaplane taxiing in the desired direction, the pilot
then fastens the seatbelt and shoulder harness, secures
the door, and continues preparing for takeoff.

When a qualified person is available to help launch the
seaplane, the pilot can strap in, close the door, and start
the engine while the helper holds the seaplane. In most
situations, the helper should position the seaplane so it
is facing outward, perpendicular to the dock. It is very
important that the helper have experience in the proper
handling of seaplanes, otherwise an innocent mistake
could cause serious damage to the seaplane or to
nearby boats, structures, or other seaplanes.

TAXIING AND SAILING

One major difference between taxiing a landplane and
taxiing a seaplane is that the seaplane is virtually
always in motion, and there are no brakes. When
idling, a landplane usually remains motionless, and
when moving, brakes can be used to control its speed
or bring it to a stop. But once untied, the seaplane
floats freely along the water surface and constantly
moves due to the forces of wind, water currents,
propeller thrust, and inertia. It is important that the
seaplane pilot be familiar with the existing wind and
water conditions, plan an effective course of action,
and mentally stay ahead of the seaplane.

There are three basic positions or attitudes used in
moving a seaplane on the water, differentiated by the
position of the floats and the speed of the seaplane
through the water. They are the idling or displacement
position, the plowing position, and the planing or step
position.

IDLING POSITION

In the idling position or displacement position, the
buoyancy of the floats supports the entire weight of
the seaplane and it remains in an attitude similar to
being at rest on the water. Engine r.p.m. is kept as low
as possible to control speed, to keep the engine from
overheating, and to minimize spray. In almost all circumstances,
the elevator control should be held all the
way back to keep the nose as high as possible and minimize
spray damage to the propeller. This also
improves maneuverability by keeping more of the
water rudder underwater. The exception is when a
strong tailwind component or heavy swells could
allow the wind to lift the tail and possibly flip the
seaplane over. In such conditions, hold the elevator
control forward enough to keep the tail down.
[Figure 4-5 on next page]

Use the idling or displacement position for most taxiing
operations, and keep speeds below 6-7 knots to
minimize spray getting to the propeller. It is especially
important to taxi at low speed in congested or confined
areas because inertia forces at higher speeds allow the
seaplane to coast farther and serious damage can result
from even minor collisions. Cross boat wakes or swells
at a 45° angle, if possible, to minimize pitching or
rolling and the possibility of an upset.